Field of the Invention
This invention relates to a water conditioner apparatus such as a water softener or an iron and/or sulfur filter.
In general, water conditioners or iron and/or sulfur filters include a tank containing a particulate material for softening water by removing calcium and magnesium salts, or iron and/or sulfur from the water. Such apparatuses generally have four cycles of operation, including a service cycle in which water is filtered through a bed of particulate material for use, a backflush cycle in which contaminants are removed from the bed, and a regeneration cycle in which the particulate material is regenerated and a rinse cycle to stabilize and flush the bed.
During the service cycle, water flows in one direction through the bed and is discharged from the bed through a dip tube or the like. During backwashing, the flow of water is reversed, i.e., water flows in the other direction through the dip tube into the bed and upwardly to "lift" the bed, i.e. placing the bed in suspension and causing agitation to dislodge bed contaminants, which are drained from the top of the tank. During the regeneration cycle, fresh chemicals are introduced into the tank to recharge the particulate material. In the case of a water softener, the active ingredient introduced into the bed of particulate material is sodium or potassium chloride.
In the case of an iron and/or sulfur filter, potassium permanganate (KMnO.sub.4) is used to regenerate the bed.
A problem with water conditioner apparatuses of the above described type is that of complete use of the bed of particulate material during each cycle of operation. Specifically, during the service and regeneration cycles, liquid flowing through the tank seldom contacts any more than 30-70% of the particulate material. Moreover, during backwashing recycled particulate bed material is often not evenly distributed in the tank, depleting or exhausting bed capacity unevenly and reducing bed efficiency. With conventional dip tube type apparatuses, it has been found that chemicals added during regeneration or salting cycle tend to hug the dip tube, contacting a relatively small proportion of the bed. The same thing happens in the service cycle.
A water conditioner and backwash device addressing this problem is described in detail in U.S. Pat. No. 5,472,609. This patent is incorporated herein by reference. Examples of other apparatuses of this type are found in U.S. Pat. No. 3,395,099, issued to R. D. Johnson on Jul. 30, 1968 and U.S. Pat. No. 3,455,458, issued to R. D. Johnson on Jul. 15, 1969. The Johnson devices employ separate, spaced apart tubes. In one embodiment of the Johnson inventions, during backwashing particulate mineral is drawn into one of the tubes in a limited area beneath the tube. The other Johnston device involves separate, parallel tubes or a spiral tube on a second tube. In each case, suction for backwashing is created by means of a fine nozzle. It has been found that such devices become clogged to the point of inoperability. Moreover, such prior art devices cannot be used with some commercial water treatment control valves with up flow brine controls, because the regenerative chemical will by-pass the bed by flowing up through the second tube, by passing the bed.
Devices for distributing fluid in particulate bed filter apparatuses are described in U.S. Pat. No. 3,240,699, issued to J. H. Duff et al on Mar. 15, 1966; U.S. Pat. No. 3,402,126, issued to Y. R. Cioffi on Sep. 17, 1968; U.S. Pat. No. 3,429,443, issued to H. B. Stern on Feb. 25, 1969; U.S. Pat. No. 3,451,554, issued to C. E. Wade on Jun. 24, 1969; U.S. Pat. No. 3,455,458, issued to R. D. Johnston on Jul. 15, 1969; U.S. Pat. No. 3,747,768, issued to S. E. Barrera on Jul. 14, 1973; and U.S. Pat. No. 3,809,247, issued to J. E. Brett on May 7, 1974.
Some of the distribution devices described in the above-identified patents are somewhat complicated and/or difficult (if not impossible) to install in existing particulate bed apparatus. Accordingly, a need still exists for an efficient distribution device which ensures even distribution of fluid and particulate solid during the service, regeneration and backwashing cycles of a water conditioner containing the bed.